1. Field of the Invention
The present invention generally relates to a document supplying apparatus for supplying a document retrieved from a set of documents in response to a request, a document supplying system having such document supplying apparatus implemented therein, a program for causing a computer to perform the function of the document supplying apparatus, and a machine-readable storage medium having such a program embodied therein.
2. Description of the Related Art
Patent Documents 1 through 5 disclose examples of technologies for performing the automatic masking of letters or the like.                [Patent Document 1] Japanese Patent Application Publication No. 2001-142893        [Patent Document 2] Japanese Patent Application Publication No. 2002-259363        [Patent Document 3] Japanese Patent Application Publication No. 2002-2593.68        [Patent Document 4] Japanese Patent Application Publication No. 11-143871        [Patent Document 5] Japanese Patent Application Publication No. 2002-312362.        
Information that can be used to identify individuals or organizations, such as the names, telephone numbers, mail addresses, or the like of individuals or organizations, needs to be handled with sufficient care since such information relates to privacy. In recent years, particularly, there has been a trend in which the sharing of information inside/outside organizations is advanced to improve the efficiency of business. This creates an environment in which information is easy to be distributed to third parties through the sharing of information.
There is an increasing awareness that privacy and confidential information need to be protected. Because of this, the sharing of documents including such information is aborted in some cases. This may serve as a factor that hampers the trend toward the sharing of information.
If the sharing of information is to be advanced, there may be a need to manually erase or mask sensitive portions that relate to privacy and confidential information. This increases costs, and may present a situation in which error by oversight occurs.
A technology for processing documents as image information is known as a means to counter such shortcomings. A means to mask sensitive portions in an image is sometimes provided in a scanner, a copier, etc., but requires a manual input for identifying the area to be masked. The trouble of manual labor still remains.
A technology for processing sensitive portions as a unit of information, rather than as an image, is also known. For example, there is a technology for masking particular fields in table format data (e.g., Kanjou Bugyou Series by OBIC (registered trademark)), and also a technology for allowing an area to be specified at the time of document creation (e.g., Ichitaro by JUSTSYSTEM (registered trademark)). The use of such table format information, however, has a shortcoming in that other types of formats cannot be used.
The technologies disclosed in Patent Documents 1 through 3 are directed to the automatic masking of letters or the like. These technologies of Patent Documents 1 through 3 automatically extract proper nouns from information by applying morphological analysis or the like, and process the extracted portions through the masking of letters or the like. In this case, no data about the users to whom the information is supplied is given, so that the masking of letters is carried out indiscriminately with respect to all the users. The creator of the document and trusted parties should be treated differently from third parties in terms of whether to mask the information. Despite this, these technologies described here cannot provide such discriminatory treatment of parties.
Patent Document 4 discloses a technology for applying blurring to a registered document based on profile information that is carried by a party who is accessing the document. This technology can control the range of information disclosure according to the conditions of a party who is requesting the information. However, the party who is accessing the information needs to bear the trouble of carrying a profile. Further, no consideration is given to differences between the creator of the document, the person having registered the document, and third parties.
The technology disclosed in Patent Document 5, on the other hand, determines whether to mask information by using information about the organization to which a person having registered the document belongs and by comparing this information with information about the organization to which the creator of the document belongs. This technology utilizes information about organizations when determining whether to mask information. There is a need, however, to provide descriptions of all the members in advance belonging to the organizations to which information can be presented. This is cumbersome.
Further, this technology defines expressions to be masked solely based on organizational information. This ends up treating all documents in the same manner, giving no consideration to the types of documents.
Accordingly, there is a need for a mechanism for easily controlling document disclosure levels according to a person who is requesting access.
There is another need for a mechanism for easily controlling document disclosure levels according to the types of documents.